1. Field of the Invention
The present invention relates to a door pull having an opening assistance mechanism and a sash window.
2. Description of Related Art
An opening assistance mechanism has been proposed in which a trigger protruding from the door stopper stile of a shoji (paper sliding door) towards a jamb, linked with the operation of a door pull for opening the shoji, pushes the jamb to help the opening operation of the shoji (see, for example, Reference Material 1, Japanese Patent Laid Open publication No. Hei 10-184185, pages 3-4, FIGS. 7-10).
According to the opening assistance mechanism disclosed in Reference Material 1, a cylindrical body fixed on the door pull is introduced in an oblong hole of an oscillating body supported by means of a shaft provided in the housing within the door stopper stile, and an operation of the door pull will cause the oscillating body to move in any circular directions. In conjunction with the circular motion, a first magnet is linked slidably in the vertical direction with the oscillating body. Also, a second magnet is mounted on the trigger facing the first magnet, and the attraction or the repulsion of these magnets causes the trigger to project and retroject. Therefore, sliding the door pull in the opening direction of the shoji results in the vertical sliding of the first magnet linked with the oscillating body, and the repulsion of the trigger magnet to the first magnet causes the trigger to project from the door stopper stile to kick the jamb, which helps the opening operation of the shoji.
According to another embodiment of the opening assistance mechanism disclosed in Reference Material 1, a cylindrical body fixed on the door pull is linked with a first rack provided in the housing within the door stopper stile, and this first rack is engaged with a pinion supported by a shaft within the housing. The pinion is engaged with a second rack, and a trigger fixed on this second rack is designed to project and retroject from the door stopper stile as the pinion rotates. Therefore, in this embodiment also, sliding the door pull in the opening direction of the shoji causes the trigger to project from the door stopper stile to kick the jamb through the first rack, pinion and second rack, which helps the opening operation of the shoji.
However, the opening assistance mechanism disclosed in the Reference Material 1 above involves a problem in that its construction is complicated and requires a large number of component parts.